1. Field of the Invention
The present invention generally relates to devices and methods for manipulating piping, and more particularly to a method and system for assembly and disassembly of pipes in and on the ground.
2. Discussion of the Background
In many agricultural and horticultural settings, rigid, above-ground, portable sprinkler systems are used for irrigation of crops, pasture, trees, or grasses, etc. These systems have, over the years, replaced many other forms of irrigation, such as flood irrigation, because they minimize erosion, prevent many drainage problems, do not require land leveling, and generally provide a uniform application of moisture to irrigate crops on a variety of terrains and minimal management expertise while conserving water. Sprinkler irrigation systems are typically constructed from modular sections of either aluminum or polyvinyl chloride (PVC) that include pipes, risers, sprinkler heads and connectors that are assembled and disassembled in the field as needed.
One common irrigation system, often called a “solid-set” system, includes a main line that provides water to a plurality of lateral irrigation lines. Each lateral line has a plurality of sprinkler heads positioned to irrigate a field. In some solid-set systems, the lateral lines provide water to the entire field. Other solid-set systems, the lateral lines provide water to only a portion of the field, and the lateral lines are disassembled and then reassembled at different positions along the main line as needed. When the irrigation season is over, the solid-set system may be disconnected and stored so that the crops may be harvested and the ground may be worked in preparation for the next growing season.
Examples of prior art solid-set irrigation systems are shown in FIGS. 1-4 where: FIG. 1 shows a top schematic view of a system 100 for irrigating a field with a single set-up; FIGS. 4A and 4B show top schematic views of another prior art solid-set irrigation system using multiple set-ups as a first system 100′ and a second system 100″; FIG. 2 is a perspective view of FIGS. 1, 4A and 4B, and FIG. 3 is a perspective view of a specific coupler.
With reference to FIG. 1, system 100 includes a main line 110 that accepts a flow of water W from a pump (not shown) and that has a length M over which water is delivered to several lateral irrigation lines 120 each having a length L and arranged parallel on a field. Thus, for example, it is common to use a solid-set irrigation system to irrigate row crops having, for example, lateral lines with sprinkler heads on 30 or 40 foot linear spacing and 40 feet between lateral lines, and the length L can be from 20 feet to half a mile. Typically, the diameter of irrigation main line 110 is from 6 to 12 inches and the diameter of lateral lines 120 are from 1½ to 4 inches. Alternatively, the length and/or pattern of lateral lines 120 can be different from line to line to irrigate an irregular shaped plot of land.
With reference to FIGS. 4A and 4B, first and second systems 100′ and 100″ have a main line with several connectors (113a, 113b, 113c, 113d, 113e, and 113f) and two lateral lines (120a and 120b). By moving lateral lines 120a and 120b from the position shown in system 100′ to the position shown in system 100″ the entire field may be irrigated by sequentially watering different portions at a time. Thus system 100′ has lateral line 120a joined to connector 113a and lateral line 120b is joined to connector 113d, irrigating only a portion of the filed. At a later time, the solid-set system is reconfigured as system 100″, with lateral line 120a joined to connector 113b and lateral line 120b is joined to connector 113e, thus irrigating a different portion of the field.
Irrigation systems 100, 100′, and 100″ are formed from a collection of modular pipe, coupler, and sprinkler segments. Thus, for example, main line 110 includes a plurality of main line pipe segments 111, with adjacent segments are joined by one of a plurality of couplers 113. Each lateral line 120 includes a plurality of lateral pipe segments 121, with adjacent segments joined by one of a plurality of couplers 123. Each lateral line 120 extends length L from an end 112 that is connected to main line 120 at one of couplers 123 to another end 114. As shown in FIG. 2, each connector 123 is also attached to a riser 125 that protrude from the field and terminates with a sprinkler head 127. Commonly used materials include aluminum, polyethylene, or PVC tubing, and stainless steel and/or polyethylene or nylon fittings.
One particularly useful solid-set irrigation system includes tubing and couplers of PVC, such as the YELOMINE™ CERTA-LOK™ main line and the YELOMINE™ CERTA-SET™ lateral line systems, manufactured by the Certain Teed Corporation, Pipe and Plastics Group, Valley Forge, Pa. In these solid-set systems, pipe segments are joined using coupling devices that allow for rapid breakdown and packaging of the system. This system is particularly easy to use, as the pipes are spline-coupled—that is, they are held together with “splines” that are inserted into the coupler. The couplers include an o-ring to seal against an accepted pipe, and the couplers and pipe ends have matching circumferential grooves for accepting the spline. The spline is a flexible elongated strip the fits within the matching circumferential grooves and that, when inserted, keeps the joint together by preventing relative lateral motion.
An example of a CERTA-LOK™ or CERTA-SET™ pipe and coupler is illustrated in the perspective view of FIG. 3. A pipe 2, such as lateral line 120, is shown as being formed from tube or pipe segments 1, indicated as a first pipe segment 1a and a second pipe segment 1b joined by a coupler 3. Coupler 3 also includes an adapter 4c for accepting lateral pipes, such as a riser 5 terminated by a sprinkler head 7. Alternatively, pipe 2 can be main line 110 with adapter 4c configured to accept a lateral line 120, or coupler 3 can be configured to joint adjacent segments without an adapter to another pipe or riser.
Coupler 3 has a first end 4a for accepting first pipe segment 1a and a hole 6a for inserting a spline 8, such as a first spline 8a, and a second end 4b for accepting second pipe segment 1b and a hole 6b for inserting spline 8, such as a second spline 8b. When each end 4a, 4b accepts an end of a pipe segment 1a, 1b, grooves within each end and the corresponding end of pipe segment 1a, 1b form a groove for accepting an inserted spline 8a, 8b to laterally restrain the pipe segments. Removal of a spline 8 allows for removal of the corresponding pipe segment 1 from the coupler.
When properly seated, the groove can accept a spline that is removably insertable through the side of the coupler. An accepted spline nearly encircles the pipe and coupler and prevents relative longitudinal movement of the pipe and coupler. Coupling is accomplished by pushing the pipe and coupler together and inserting a spline. Decoupling is accomplished by pulling a spline from the coupler of a coupled pipe and pulling the pipe and couplers apart. A sprinkler having a reactionary drive mechanism may be coupled to any of the couplers through quick coupling risers, or by pinning or threading.
The assembly or disassembly of solid-set irrigation systems is commonly performed by arranging pipe segments and coupling or decoupling them, respectively. The assembly and disassembly is usually performed manually in the field. Although the advent of PVC solid-set irrigation systems is lighter and couples more easily that metal irrigation systems, such systems still require considerable time and effort for assembling and disassembling. This work includes the placement and movement of heavy and bulky pipe segments that requires teams of workers. After irrigation the pipe segments are embedded in the mud, making movement difficult. The manual manipulation of piping requires a lot of work that is difficult to do on a timely basis. Occasionally the work results in injury to the workers and delays due to mud in the field.
Some devices have been proposed to automate the assembly irrigation pipes. These systems require the movement of pipe segments, couplers and risers across the field. Such systems are not useful for systems requiring the movement of lateral lines during a growing season since the use of the devices would disrupt large portions of the cultivated field.
Other devices have been proposed to automate the disassembly of irrigation pipes by grabbing portions of the pipe and pull them out of the field. These systems can damage piping and are not useful for assembling pipe. In addition, these other devices are typically too wide to fit the existing head lands of the field.
While the use of solid-set irrigation systems has greatly improved the ability to irrigate, and while plastic piping, such as PVC piping has made such systems more robust and easier to assemble and disassemble, there are still several problems. Thus, for example, the assembly and disassembly is either performed manually by teams of workers or by proposed devices that are not useful for all uses and applications.
Thus there is a need in the art for a method and apparatus that permits for the easy assembly and disassembly of modular piping systems. Such a method and apparatus should be compatible with existing piping systems, be useful for a variety of solid-set irrigation set-ups, facilitate the coupling or decoupling of pipe components, and should not damage the pipe or components. There is also a need for a system and method for removing piping from the field while the field is still wet.